1. Field of the Invention
This invention relates to an air conditioner equipped with an air cleaner.
2. Description of the Related Art
Recently, in order to improve the function of an air conditioner, intensive research has been conducted on an indoor unit which is equipped with an electronic dust collector. As is well known, the electronic dust collector is so designed that with high voltage applied between a discharge electrode and a dust collecting electrode, dust in the air is ionized by the discharge electrode, thus being adsorbed to the dust collecting electrode. With the dust collector equipped with the indoor unit of the air conditioner, the air conditioner has not only its original air conditioning function, but also an air cleaning function.
In the air conditioner, the position of installation of the dust collector is normally between the front grill and the heat exchanger which is provided behind it; that is, the front of the heat exchanger. In addition, Japanese Patent Unexamined Publication No. Sho. 64-28427 has disclosed the following air conditioner: In order to improve the dust collecting efficiency in the case where the dust collector is provided in front of the heat exchanger, dust collection is carried out in such a manner that, in front of the heat exchanger, the air is caused to flow upwardly in a zig-zag manner.
On the other hand, with respect to the cleaning of the dust collecting electrode which is a problem given to the dust collector, a maintenance-free type dust collector has been proposed in which a heater is mounted on the dust collecting electrode to burn and remove the dust stuck onto the dust collecting electrode.
By the way, the fundamental structure of the dust collector is the combination of a linear discharge electrode and a planar dust collecting electrode. A conventional air conditioner with an air cleaner in which the dust collector is installed in front of the heat exchanger of the air conditioner suffers from a problem that the suction of air is interrupted especially by the planar dust collecting electrode, so that its original air conditioning function is lowered.
That is, in the case where the dust collector is mounted in front of the heat exchanger of the air conditioner, normally the planar dust collecting electrode is provided above or below the linear discharge electrode, and the dust collecting electrode is provided along the surface of the heat exchanger. The reasons why the dust collecting electrode is provided along the surface of the heat exchanger are for instance as follows: The increase in depth of the air conditioner can be avoided. Also, in the case where an air cleaning operation is carried out with ion wind during the stop of the air conditioning operation, the flow of weak ion wind can be prevented from being interrupted by the dust collecting electrode. By the provision of the dust collecting electrode along the surface of the heat exchanger, the suction of air into the heat exchanger is interrupted; that is, the original air conditioning function is lowered.
This problem that the air conditioning function is lowered is significantly great especially when the maintenance-free type dust collector is used in which the dust collecting electrode is combined with the heater. That is, in the maintenance-free type dust collector, normally the heater is combined with a heat shielding plate or the like, and therefore, the ventilation resistance by the dust collector is further increased, and accordingly the suction of air into the heat exchanger is further interrupted. Hence, in the air conditioner with the air cleaner which employs the maintenance-free type dust collector in which the dust collecting electrode is combined with the heater, the decrease in the original air conditioning function is a great problem.
As is disclosed in Japanese Patent Unexamined Publication No. Sho. 64-28427, it goes without saying that also in the case where the dust collecting operation is carried out while the air is caused to flow in front of the heat exchanger upwardly in a zig-zag manner, a decrease in the air conditioning function is a problem.